Talk:Programming UNROM: Difference between revisions
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* A few games (notably ''Low G Man'') require the PRG RAM to be absent. | * A few games (notably ''Low G Man'') require the PRG RAM to be absent. | ||
What's ambiguous about mappers 2 (UxROM), 3 (CNROM), and 7 (AOROM), other than whether or not the ROM has a positive chip enable to avoid bus conflicts? --[[User:Tepples|Tepples]] ([[User talk:Tepples|talk]]) 22:19, 26 February 2013 (MST) | What's ambiguous about mappers 2 (UxROM), 3 (CNROM), and 7 (AOROM), other than whether or not the ROM has a positive chip enable to avoid bus conflicts? --[[User:Tepples|Tepples]] ([[User talk:Tepples|talk]]) 22:19, 26 February 2013 (MST) | ||
: Two things- | |||
:# the comment about PRG-RAM: due to iNES's shortcomings one can't distinguish between 0="no ram" and 0="unspecified ram"; and | |||
:# the entire point behind NES2.0's backwards compatibility is the encouragement of its adoption without infringing on non-NES2.0-aware emulators. Creating mindshare makes it possible to say that it really is a solution.—[[User:Lidnariq|Lidnariq]] ([[User talk:Lidnariq|talk]]) 01:50, 27 February 2013 (MST) | |||
Revision as of 08:50, 27 February 2013
NES 2.0 advocacy
Converting a ROM from original iNES to NES 2.0 isn't strictly necessary unless the mapper is ≥ 256 or the iNES header is ambiguous. For example:
- Several VRC mappers are ambiguous as to which low CPU address lines are connected to the mapper's port select.
- Mapper 1 is ambiguous between SIROM (PRG A14 from MMC1 output) and other SxROM boards using 32K PRG (PRG A14 from CPU A14).
- Mappers 1, 4, and 5 are ambiguous among PRG RAM sizes. For example, SNROM vs. SOROM, MMC3 vs. MMC6.
- A few games (notably Low G Man) require the PRG RAM to be absent.
What's ambiguous about mappers 2 (UxROM), 3 (CNROM), and 7 (AOROM), other than whether or not the ROM has a positive chip enable to avoid bus conflicts? --Tepples (talk) 22:19, 26 February 2013 (MST)
- Two things-
- the comment about PRG-RAM: due to iNES's shortcomings one can't distinguish between 0="no ram" and 0="unspecified ram"; and
- the entire point behind NES2.0's backwards compatibility is the encouragement of its adoption without infringing on non-NES2.0-aware emulators. Creating mindshare makes it possible to say that it really is a solution.—Lidnariq (talk) 01:50, 27 February 2013 (MST)
